Black Sabbath are an English rock band, formed in Aston, Birmingham in 1968 by Ozzy Osbourne (lead vocals), Tony Iommi (guitar), Geezer Butler (bass guitar), and Bill Ward (drums). The band has since experienced multiple line-up changes, with Tony Iommi the only constant presence in the band through the years. A total of twenty-two musicians have at one time been members of Black Sabbath. Originally formed as a heavy blues-rock band named Earth, the band began incorporating occult- and horror-inspired lyrics with tuned-down guitars, changing their name to Black Sabbath and achieving multiple platinum records in the 1970s. Despite an association with occult and horror themes, Black Sabbath also composed songs dealing with social and political issues such as drugs and war.